Preparation of Crown Ether Pillared Zirconium Phosphonate and Selective Adsorption for Strontium

Abstract

Separation of strontium isotope is an important and challenging work. Herein, a novel method was developed for preparing of acid-resistance crown ether pillared zirconium phosphonate (D-AM-ZrP) by a directly one step reacting 4-amino-benzo-18-crown-6 phosphonic acid with zirconium other than the conventional complicated intercalation methods. By suitable control of the ratio of phosphoric acid to phosphonic acid, the D-AM-ZrP sample with perfect flower-like and well-ordered interlayer structure was obtained. More importantly, D-AM-ZrP exhibited high adsorption capacity and excellent selectivity for extracting Sr2+ from complicated system including high concentrated HNO3 media and competing ions, and the maximum adsorption capacity for Sr2+ (136.42 mg·g-1) was better than that of pure α-ZrP (28.17 mg·g-1) at weak acidic media, which could mainly be attributed to the presence of the strong chemical interaction between the intercalated molecule and material, resulting in its excellent stability and abundant adsorption sites.

Keywords

• intercalation
• crown ether
• zirconium phosphonate
• adsorption
• sr2+